Drinking water is commonly packaged and sold in large glass or plastic bottles having volume capacities of about 5 gallons. The containers are very bulky and heavy, weighing about 50 lbs. each.
Because of their bulky size and weight, personnel who deliver these products find it convenient to use a hand truck when transporting these products from the delivery truck to the consumer's home or place of business. A conventional two-wheeled hand truck of the type having a single load-supporting nose piece projecting forwardly from the bottom of the frame can handle a single 5-gallon bottled water container. Another such two-wheeled hand truck is known in which multiple, foldable trays are provided that are pivoted to the side rails of the truck and which can be folded down to extend forwardly of the frame for carrying up to four bottled water containers on the hand truck.
Convertible bulk hand trucks are also known having a main frame and a foldable sub-frame that, when folded together, form a two-wheeled dolly device or hand truck and, that, when unfolded, form a four-wheeled cart as shown, for example, in U.S. Pat. Nos. 3,785,669; 4,921,270; and 5,536,034. When in the four-wheeled cart position, the horizontal main frame portion forms a flat, planar platform or bed for supporting cargo to be transported. It will be appreciated that while such a platform is well suited for supporting boxes and other objects with flat support surfaces, it would not be well suited for carrying cylindrical bottled water containers, as they would have a tendency to roll or shift about and be generally unstable.